“There are many applications for ultracold neutrons in fundamental physics,” Oliver Zimmer tells PhysOrg.com. “And we will find even more applications with a stronger source of ultracold neutrons.” Zimmer, a scientist at the Institut Laue Langevin in Grenoble, France, thinks that he and his colleagues may have found a way to tap a better source for ultracold neutrons by extracting them from superfluid helium.